Growth and photosynthesis of plants in response to environmental stress. [Raphanus sativus; Glycine max; Salix nigra; Alnus serrulata; Populus tremuloides]

Miscellaneous · Tue Jan 01 00:00:00 EST 1991

OSTI ID:6913436

Greitner, C S

Environmental stresses generally decrease photosynthetic rates and growth of plants, and alter biomass partitioning. Nutrient deficiency and drought cause root:shoot ratios to increase, whereas the air pollutant ozone (O[sub 3]) causes an opposite shift in carbon allocation. Plants in nature usually grow under suboptimal conditions; therefore plants were raised with O[sub 3] combined with other stresses to analyze the mechanisms whereby multiple stresses influence gas exchange and growth. Physiological and growth responses to stress were determined for radish (raphanus sativus), soybean (Glycine max) willow (Salix nigra), alder (Alnus serrulata) and aspen (Populus tremuloides) in laboratory and field trials. In willow, high-nutrient status plants had more visible injury, but a smaller decline in leaf area with O[sub 3] than did low-nutrient plants. Ultrastructure of host plant cells in alder root nodules was disrupted by O[sub 3], suggesting that this air pollutant can affect the ability of plants to acquire nutrients via symbiosis. Biomass and root:shoot ratios decreased with O[sub 3] in radish and soy-bean. Shifts in stable carbon isotope ratios were caused by O[sub 3], and this technique was used to integrate the effects of O[sub 3] on gas exchange over time. In aspen, O[sub 3] enhanced photosynthesis and foliar areas in young leaves of well-watered aspen, partially compensating for declines in older leaves. This effect was more pronounced in plants raised at a high nitrogen level than in N-deficient plants. Carboxylation efficiency decreased in older, but increased in younger leaves with O[sub 3]. Prior exposure to drought reduced effects of O[sub 3] on photosynthesis and leaf area.

• Research Organization: Oregon State Univ., Corvallis, OR (United States)
• OSTI ID: 6913436
• Resource Relation: Other Information: Thesis (Ph.D.)
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
OZONE
TOXICITY
PLANTS
BIOLOGICAL STRESS
AIR POLLUTION
GLYCINE HISPIDA
INHIBITION
NUTRIENTS
PHOTOSYNTHESIS
PLANT GROWTH
CHEMICAL REACTIONS
GROWTH
LEGUMINOSAE
MAGNOLIOPHYTA
MAGNOLIOPSIDA
PHOTOCHEMICAL REACTIONS
POLLUTION
SYNTHESIS
560300* - Chemicals Metabolism & Toxicology